One well-known application of density is determining whether or not an object will float on water. If the object's density is less than the density of water, it will float; if its density is less than that of water, it will sink.In fact, submarines dive below the surface of the water by emptying their ballast tanks
Answer:
Option C
100 J
Explanation:
Kinetic energy, KE is given by
where m is the mass and v is the velocity
Substituting 50 Kg for mass, m and 2 m/s for velocity v then we obtain

Therefore, the child's kinetic energy is equivalent to 100 J
Answer:No, it doesn't move easily downward because it will try to resist the movement ,due to a resistance force of inertia that it possess at rest.
Explanation:when an object has higher or larger mass it tends to resist any motion given to it unlike the one with lower mass.
The larger the mass the more resistance force an object has.
That is true Step by step: